1. Field of the Invention
The present invention is directed to and proceeds from a method for determining the time position of a synchronization sequence in a received data stream (frame synchronization) according to the preamble of the generic claim.
2. Description of the Prior Art
A frame synchronization method of this general type is known (James L. Massey, "Optimum Frame Synchronization", IEEE Trans. on Comm., Vol. Corn. 20, April 1972, pp. 115-119 and R. Mehlan, H. Meyr, "Optimum Frame Synchronization for Asynchronous Packet Transmission", ICC 1993 in Geneva, Vol. 2/3, pp. 826-830). This type of frame synchronization method has the disadvantage that a clock, carrier and phase synchronization must be implemented before the actual frame synchronization. A carrier and phase synchronization without previously implemented frame synchronization and, thus, without knowledge of the data sequence, is only possible with methods known as Non-Data-Aided (NDA) methods. The theoretically allowed frequency deviation between transmitter and receiver given the transmission of higher level MQAM signals amounts to 12.5% of the symbol rate in such NDA methods and even amounts to only 1/M .multidot.50% in MPSK. In TDMA transmissions, only the burst itself is available to be employed for clock, phase and carrier synchronization, and in known frame synchronization methods, the further problem exists of the time position of the burst being unknown, since the frame synchronization has not yet been implemented and can only be determined by additional auxiliary measures.